In one aspect, this invention relates to a diaphragm. In another aspect, this invention relates to a valve. In still another aspect, this invention relates to a drill bit containing a lubrication system including a relief valve.
Drill bits employed in the oil and gas industry typically utilize rolling cutters on the lower end of the bit. The rollers are mounted on bearings or bushings which must be supplied with lubricant in order to prevent premature failure.
Lubricant systems which have been devised to provide such a supply of lubricant typically include a pressure compensator system to maintain the lubricant at approximately the same pressure as the borehole fluids surrounding the drill bit. By equalizing the pressure across the lubricant system seals and across the compensator system diaphragm, the risk of system failure is reduced.
Particularly to protect the seals of the lubricant system against increases in pressure from the lubricant side, however, a relief or vent system is still considered very desirable.
It is an object of this invention to provide a valve for venting a drill bit lubricant system.
It is a further object of this invention to provide such a valve which is capable of being manufactured, tested and shipped apart from the bit.
It is another object of this invention to provide a relief valve which can be easily modified to vent at different pressures, or to check flow in one direction if desired.